It will take City of Kitchener forestry crews "at least three to four weeks" to clean up after a violent storm hit Waterloo Region and damaged thousands of local trees. 

Kim Nihls, the City of Kitchener's supervisor of forestry, told CBC's Craig Norris on The Morning Edition he doesn't yet know the full extent of the damage — either in terms of the number of lost trees or final financial cost to the city.

Among the losses: three very large, mature chitalpa trees — which Nihls estimates were between 100 and 200 years old —uprooted from Victoria Park.

"A large tree provides so much more benefit than a whole bunch of small little trees as far as the carbon dioxide taking in, and the shade provided," he said.

"You always replace the tree once it's been taken down but the real big ones really aren't replaceable," he said.

Trees in Waterloo Park also saw significant damage, said Waterloo City councillor Melissa Durrell. The park is covered with branches and half-fallen trees.

"It is a crying shame that some of these old healthy trees were really the ones that were treated the worst," said Durrell.

She said the city will begin trying to figure out a plan to replace the trees in Waterloo Park and Uptown Waterloo before the end of the week.